Study on the Lateral Performance of Large-Scale Steel Casing-Reinforced Concrete Pile Composite Members

In order to investigate the lateral working performance of large-scale steel casing-reinforced concrete pile composite members, this paper sets up large-scale steel casing-reinforced concrete pile composite members with different slenderness ratios λ, compressive axial force ratios N, and foundation strengths. It conducts quasi-static loading tests to investigate the effects of these factors on the hysteretic performance, bearing capacity, ductile performance, strength degradation, and stiffness degradation of the members. The results show that the hysteresis curves of the members all have a typical inverse S-shape, which is affected by slip and has a poor degree of fullness. The members with larger slenderness ratios exhibit better ductility performance, deformation performance, and energy dissipation performance, but their poorer bearing capacity and effect on stiffness degradation are limited. While members with smaller slenderness ratios exhibit better bearing capacity, their ductile performance is poor. As the compressive axial force ratio increases, the lateral bearing capacity and ductility of the members slightly improve. However, the bearing capacity rapidly decreases when the compressive axial force ratio reaches a critical value. As the strength of the foundation increased, the lateral bearing capacity of the structures continued to improve, but its improvement effect began to decay after reaching a certain value. This paper investigates the lateral working properties of large-scale steel casing-reinforced concrete pile composite members designed for overhead vertical wharves that are subjected to significant water level differences in inland rivers, aiming to provide a reference for their application in practical engineering.